P&O Ferries has announced it is preparing to restart sailings “from this weekend” on routes suspended since it sacked nearly 800 seafarers.
The firm revealed plans to resume operations for four of its ships, including between Cairnryan and Larne.
The European Causeway that serves the Scotland to Northern Ireland crossing failed an inspection by the Maritime and Coastguard Agency last month, but P&O said it expects it to return to service.
The route is currently suspended up to and including April 11.
P&O has been prevented from running all but one of its vessels since it announced widespread redundancies on March 17.
It caused outrage by replacing its crews with cheaper agency workers, without notice, with many employees notified via video call.
A spokesman for the firm said: “From this weekend, P&O Ferries are getting ready to resume services across a number of vital routes.
“P&O has been working closely with regulators to ensure our ships are safe to sail.
“P&O is looking forward to welcoming back vital services and we expect to have two of our vessels ready to sail on the Dover/Calais route by next week, subject to regulatory sign-off, namely both the Pride of Kent and Spirit of Britain between Dover/Calais.
“P&O are also expecting to be able to sail both the European Causeway, which runs between Larne and Cairnryan, and the Pride of Hull, which runs services between Hull and Rotterdam.”
He added: “We thank our customers for their patience during this time and we apologise to those customers whose journeys have been cancelled and disrupted.”
The announcement comes as a former P&O Ferries chef is reportedly suing the company for unfair dismissal, racial discrimination and harassment.
The ferry operator is under criminal investigation over the sacking of nearly 786 seafarers.
The Insolvency Service confirmed it had commenced formal criminal and civil investigations into the circumstances surrounding the redundancies.
P&O Ferries chief executive, Peter Hebblethwaite, told a joint hearing of the Commons’ business and transport committees that his company broke the law by not consulting with trade unions before sacking workers.